The (p, V-m, T) behaviour of (heptane + 1-chlorobutane) was measured at the temperatures (298.15, 308.15, 318.15, and 328.15) K and in the pressure range 0.1 to 40 MPa with an accuracy in density of +/-1 (.) 10(-4) g cm(-3). An apparatus for the (p, Vm, T) measurement of liquids and liquid mixtures whose main part is a high-pressure vibrating-tube densimeter working in a static mode was used for the measurement. Excess molar volumes were calculated from the data and fitted to the Redlich-Kister equation.